The invention relates to a floor cleaning device of the vacuum cleaner type wherein a rotatable brush is used to dislodge dust and dirt on a floor covering, in a region wherein a partial vacuum is maintained by an air suction device to remove the dislodged dust and dirt. It has long been desired to construct such devices is as to clean a floor covering without leaving dusty and dirty margins and corners.
In earlier brush-type vacuum cleaners the housing structure for the brush was wider than the area effectively brushed. Therefore, dusty and dirty margins and corners unavoidably remained in the use of the earlier devices. In some types of such devices this was due to the provision of drive means, for example of a gear transmission and bearings, along side walls of the housing. In later models, the drive means, bearings and the like were located in the housing; but margins and corners of the floor coverings were still not cleaned effectively. This was particularly so since the side walls still had to provide any desired means for adjusting the brush relative to the housing and/or means to permit replacement of the brush when the bristles were worn. In some cases, the brush adjusting structures included support wheels for the housing and various linkages for raising or lowering the brush relative to the housing; those wheels and linkages were expensive as well as unwieldy. It also was difficult in earlier constructions to operate the brush adjusting and brush releasing devices as it was necessary to use special tools or to use very considerable force for these purposes.